Support apparatus for large diameter thin-wall metal cylinders

ABSTRACT

A support assembly is disclosed for providing internal support during fabrication of thin-walled large diameter metal cylinders such as those used as membranes in concrete pipe. Such cylinders are usually 5 feet and larger in diameter. The support assembly comprises a plurality of internally mounted wheel assemblies attached to a common frame.

United States Patent 1 Lamborn et al.

SUPPORT APPARATUS FOR LARGE DIAMETER THIN-WALL METAL CYLINDERSlsa'tasiiismfe' Lassa; Glenda;

Palmer C. Gallup, Monrovia; Paul W. Kao, Covina, all of Calif.

Assignee: United Concrete Pipe Corporation,

Baldwin Park, Calif.

Filed: Feb. 15,1571 7 Appl. No.: 1 15,011

US. Cl ..72/l42, 269/48.l Int. Cl. ..B21f 3/04 Field of Search ..72/49,135, 142;

in 3,728,883 51 Apr. 24,1973

Primary ExaminerCharles W. Lanham Assistant Examiner--Robert M. RogersAttorney-Lyon & Lyon [5 7] ABSTRACT A support assembly is disclosed forproviding internal 1 support during fabrication of thin-walled largediameter metal cylinders such as those used as membranes in concretepipe. Such cylinders are usually 5 feet and larger in diameter. Thesupport assembly comprises a plurality of internally mounted wheelassemblies attached to a common frame.

18 Claims, 6 Drawing Figures SUPPORT APPARATUS FOR LARGE DIAMETERTHIN-WALL METAL CYLINDERS BACKGROUND OF THE INVENTION The inventionrelates to support apparatus for preventing the collapse or excessivedeformation of thin-walled metal cylinders of large diameter. Suchsupport means may be located adjacent to the forming device which isused to helically form a cylinder from a length of flat metal strip.When such cylinders are used in concrete pipe, their primary purpose isto form a waterproof barrier rather than to add substantial structuralstrength to the pipe. Such cylinders are typically subsequently coatedboth internally and externally with concrete, and the external concretemay later be wrapped with steel wire or cable and further coated withconcrete to form a length of prestressed concrete pipe.

Several methods have been used to prevent the collapse or excessivedeformation of large diameter helically formed cylinders. A commonapproach is to form the cylinder from a material which has a thicknesssufficient to provide structural strength against collapse or excessivedeformation of the cylinder. For example, in the case of steel cylindersof approximately 80 inches in diameter, a minimum thickness of 14 gage(0.0747 inch) generally is necessary for prevention of excessivedeformation during forming thereof. In as much as the steel cylinderperforms the function of a waterproof membrane, rather than contributingsignificant structural strength, it is apparent that a cost savings canbe achieved by the use of thinner steel.

One method of preventing collapse or excessive deformation of largediameter thin-walled helically formed cylinders is to form the cylinderon a mandrel such as that disclosed in US. Pat. No. 3,432,914. There, amandrel is wrapped during the formation stage of the process. Thisapproach requires costly equip ment, and employs a particular sizemandrel for forming each different size cylinder. Furthermore, thismandreltype approach precludes a continuous forming operation.

SUMMARY It is an object of the present invention to provide a newapparatus for preventing significant deformation of thin-walledhelically formed cylinders.

It is another object of the present invention to provide a new apparatusfor providing support of continuously formed thin-walled meta]cylinders.

It is another object of the present invention to provide an apparatusfor preventing excessive deformation or collapse of large diameterthin-walled cylinders formed horizontally and helically from metalstrip.

It is another object of the present invention to provide an assembly forproviding internal support for thin-walled cylinders, which assemblydoes not require cantilever action for horizontal support.

It is yet another object of this invention to provide an assembly whichwill provide internal support for a length of thin-walled cylinder afterit has been severed from the adjacent length of cylinder being formed.

It has been discovered that the collapse or significant deformation ofhorizontal large diameter cylinders may be prevented by providing aplurality of wheel assemblies attached to a common frame member which ispositioned inside the cylinder. For example, it has been found thatsteel cylinders as thin as 18 gage (0.0478 inch) may be formed helicallyand horizontally with a diameter as large as approximately 10 feet orlarger.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a diagrammatic plan view ofa forming device and cylinder being continuously and helically formedfrom metal strip.

FIG. 2A is an elevation view from the end of the cylinder taken forexample along line 2A-2A of FIGS. 1 or 3 showing a support assemblyaccording to the present invention.

FIG. 2B is a similar view of the support assembly from the end of asevered length of cylinder, taken for example, along a line 28-28 ofFIG. 3.

FIG. 3 is a side elevation view, partially cut away, showing the supportassembly of the present invention.

FIG. 4 is an enlarged view of one of the wheel assemblies of FIG. 2A.

FIG. 5 is a diagrammatic elevation view taken along line 5-5 of FIG. 3showing exemplary wheel locations of the support assembly of the presentinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the formation of asteel cylinder 10 which is continuously being formed from a roll ofsteel strip of skelp l 1. The strip is continuously shaped in theforming apparatus 12 into a cylinder and is continuously welded byconventional apparatus not shown. The forming apparatus 12 may be any ofthe various types which employ rollers or the like for originallyforming the strip into a cylindrical shape.

As the steel strip 11 enters the forming apparatus 12 forming devicesthereof urge the flat strip in a helical fashion into a cylindricalshape which then is welded to form a continuous cylinder. I

A mounting plate 13 may be attachedto the frame, or other structuralsupporting members, of the forming apparatus 12. A plurality of wheelassemblies as shown in FIGS. 2 and 3 are attached to an axial tube orshaft 25 which in turn may be attached to mounting plate 13.Alternatively, the axial member 25 can be attached to other suitablemeans, such as a floor mounted pedestal. As an example, six sets ofinternal wheel assemblies 15 through 20 and two sets of external wheels21 and 22 are shown in FIGS. 2A and 3. Several wheel assemblies in eachset are shown in'FIG. 2A before the length of cylinder is cut off, andthe individual exemplary wheel locations thereof may be determined byreference to FIG. 5 which will be discussed in more detail subsequently.Rollers such as 23 and 24 at the bottom of the cylinder are conventionaland function toprovide additional vertical support. The tube 25functions as a mounting member or frame for the wheel assemblies.

As shown in FIG. 3, the portion of the cylinder within the formingapparatus 12 may be supported internally by wheels 17a, 17b, 18a, 18b,15a and 17c, although in some types of forming apparatus wheelassemblies may not be necessary until the cylinder leaves the formingapparatus. Also as seen in FIG. 3, at a short distance from the formingapparatus, the cylinder is supported by wheels 15b, 16b and 17d.

The axial tube 25 is given primary vertical support, rather than relyingon cantilever action, by the lower wheel assemblies which in turn aresupported by the cylinder. The cylinder is supported in turn by lowerexternal wheels and rollers. As shown in FIG. 3, tube 25 is given upwardsupport by wheel assemblies 19a and 200 which are located inside of thecylinder. External wheel 21a is mounted to ride at the same point of thecylinder as internal wheel 19a. There is an external wheel 22a (seen inFIG. 2A, but not seen in FIG. 3) which is mounted externally and locatedso as to mate with internal wheel 20a. This combination of external andinternal wheels provides vertical support for tube 25. Wheel assembly17e, of course, provides further internal vertical support for thethin-walled cylinder 10.

At a predetermined location, a completed length of cylinder 26 (such as20 feet long) is cut as indicated at 27 in FIG. 3 from the cylinderbeing formed. This is accomplished by conventional apparatus not shown.After .the length of cylinder 26 has been severed, it nonethelessrequires internal support while it remains in a horizontal position.This internal support is provided by similar wheel assemblies mounted onthe axial tube 25 as best seen in FIGS. 2B and 3. These are shownmounted in sets of five wheels. As shown in FIG. 3, the set closest tothe forming apparatus 12 includes internal wheels 15c, 16c, 17f, 19c and20b. Internal wheels 19c and 20b have external wheels 21c and,22c (notshown) mounted externally to provide support both for the cylinder 26and for the internal set of wheel assemblies. Identical sets of fiveinternal wheels and two external wheels are located further along tube25. The wheels are caster mounted to permit them to swivel to thedirection shown in FIG. 2B and the lower part of FIG. 3 in order tofacilitate the horizontal removal of the severed cylinder 26.

The individual wheel assemblies may be of any suitable construction.FIG. 4 illustrates in detail a preferred construction. A U-bolt 30 isbolted to a saddle 31 around the axial tube 25. Pipe 32 is threaded intosaddle 31 and a hex nut 33 is welded at its other end. A threaded rod 34is screwed into hex nut 33 and a second hex nut 37 is used to securethreaded rod 34 in hex nut 33. This arrangement permits the adjustmentof the length of the arm of the wheel assembly. The swivel casterassembly 35 is screwed and welded to threaded rod 34. Swivel caster 35has a pneumatic tire 36 rotatably mounted thereon.

An example of preferred wheel locations for the sup port of anapproximately 80 inch diameter cylinder 10 of 16 gage (0.0598 inch)steel prior to the cut-off point 27 is shown in FIG. 5 for exemplaryapparatus where the strip 11 enters as shown in FIG. 2A, although otherlocations may be used in various applications. The radial locations aredescribed through the axis of rotation of the wheels. The horizontallocation of each wheel will be described starting from the mountingplate 13 and working outwardly. The angles are described in degrees of a360 circle starting at vertical line 39 and proceeding clockwise (thatis, from wheel 40 which is at zero degrees). The first wheel 17a (thatwheel closest to mounting plate 13) is in the position of wheel 47 shownin FIG. 5 and is 10 inches from the plate 13 and at an angle of 315. Thesecond wheel 18a is in the position of wheel 46 in FIG. 5. This islocated 19 inches from the plate and at an angle of 270. The third wheel17b is also at angular position 47 and is 35 inches from the plate andat an angle of 315. The fourth wheel 18b is at the angular position ofwheel 46. This is about 43 inches from the plate and at an angle of 270.The fifth wheel 15a is in the position of wheel 42 of FIG. 5. That isabout 50 inches from the plate and at an angle of 45. The sixth wheel16a is in the position of wheel 40 which is at zero degrees and is about5 8 inches from the plate. The seventh wheel 17c is in the angularposition of wheel 47 and is 68 inches from the plate. The eighth wheel15b is in the position of wheel 48 of FIG. 5. This is 72 inches from theplate and at an angle of The ninth wheel 16b is in the position of wheel49 and is about 78 inches from the plate. This is at an angle of 30. Thetenth wheel 17d is in the position of wheel 50, and is about 89 inchesfrom the plate and at an angle of about 350. The eleventh wheel 19a isin the position of wheel 45. This wheel is 102 inches from the plate andat an angle of 225. The twelfth wheel 20a is in the position of wheel 44in FIG. 5. This is 109 inches from the plate and at an angle of about152. The last wheel 17e is in position 49, and is inches from the plate13 and at an angle of 30. It will be appreciated to those skilled in theart that these are example locations and that others may be useddepending on the length of cylinder to the cut-off point, cylinderdiameter, gage of metal and so forth.

While the dimensions of the axial tube or central frame are notcritical, it has been found that for steel cylinders in the 5 to 10 footdiameter range fabricated from 14 to 16 gage steel that a 6 inch,schedule 40 pipe gives sufficient strength. For the same size range ofcylinders it has been found that a wheel assembly arm pipe 32 of 2 inchschedule 40 black iron pipe is satisfactory. A wheel assembly rod 34made from 1 if; inch stainless steel has been used. A swivel caster 35having a 4.l0/3.50-4, 4ply pneumatic tire 36 gives sufficient support.It is also possible to utilize solid rubber, plastic or steel wheels inplace of pneumatic tires. Pneumatic tires do, however, have theadvantage of creating some flexibility, in inflation thereof thus makingthe arm adjustment less critical.

The attachment of the central frame is readily accomplished by weldingthe tube 25 to a 1 inch thick flange which is then bolted to themounting platel3. The use of a U-bolt 30 or other adjustable means ofmounting to the central frame or tube 25 permits the angular and axialadjustment of wheel location dependent upon the point where the maximumsupport against deformation or collapse is desired. It has been foundbeneficial to locate the lower internal wheels at a point mating to theexternal wheels. It is not, however, necessary that each lower internalwheel have a mating external wheel and it is possible to use an externalwheel only with alternate lower internal wheels. The use of externalwheels with mating internal wheels permits the lower portion of thecylinder to support the upper portion of the cylinder since the lowerwheels provide the lateral and vertical support for the central frame ortube 25. Thus, the axial tube 25 may be of any desiredlength sincesupport thereof does not rely on cantilever action.

It has also been found desirable to provide greater lateral restraint onthe side of the cylinder represented by wheel assemblies 19a (wheelposition 45 in FIG. 5) and 21a as compared to the other side. Thisresults from the rotation of the cylinder being formed and consequentincreased force toward wheel assembly 210. Further downstream from themounting plate 13, as after the cut-off point 27, the internal andexternal support preferably is symmetrical about the vertical axis asseen in FIG. 23. However, before and after cut-off a single internalwheel mating with a single external vertical wheel (at 180 as viewed inFlG. 5), along with external wheels at approximately the locations ofrollers 23 and 24 of FIG. 2A or external positions corresponding topositions 44 and 45 of FIG. 5, may be used.

As the cylinder is removed from the last set of internal and externalsupport wheel assemblies, it is necessary that internal support beprovided until the cylinder can be placed in an upright position orotherwise supported by a coating of concrete or the like. This internalsupport may be provided by expandable light weight metal rings placedinside the cylinder, or other suitable means may be used.

The length of cylinder which can be supported by the support assembly ofthis invention is practically unlimited. Since the frame or axial tube25 does not rely on cantilever action for vertical support, the onlylimitation on length is related to resistance to twisting or torquetransmitted by the wheel assemblies. Additional torque resistance may beobtained by either the use of a larger diameter central frame or adifferent central frame configuration.

With the axial tube sizes described above, it has been found possible tomake steel cylinders as long as 24 feet. Longer cylinders can be made bythe use of this invention since additional torque resistance may bereadily provided.

The present embodiments of this invention are to be considered in allrespects as illustrative and not restrictive. The scope of the inventionis indicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims therefore are intended to be embraced therein.

What is claimed is:

1. A support assembly for providing internal support for a horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to significantly deform or collapse if without supportcomprising a plurality of circumferentially and axially spaced wheelassemblies attached to a frame member for allowing continuous rotationand axial motion of said cylinder with respect to said wheel assemblies,each wheel of said wheel assemblies being positioned for contacting adifferent portion of the inner surface of said cylinder, and

support means fixed with respect to said frame member for contacting thelower external surface of said cylinder for allowing continuous rotationand axial motion of said cylinder with respect to said support means.

2. A support assembly for providing internal support for a horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to significantly deform or collapse if without support, saidsupport assembly being held in a fixed relationship with respect to aforming apparatus, said assembly comprising a frame stationarilysupported with respect to said forming apparatus to prevent rotationalmovement of said frame and axial movement thereof in the direction ofthe axis of said cylinder, plurality of circumferentially and axiallyspaced wheel assemblies attached to said frame for allowing continuousrotation and axial motion of said cylinder with respect to said wheelassemblies, each of said wheel assemblies having at least one wheel,each wheel being substantially equidistant from the axis of saidcylinder and spaced from said axis for contacting a different portion ofthe inner surface of said cylinder, and

support means fixed with respect to said frame member for contacting thelower external surface of said cylinder for allowing continuous rotationand axial motion of said cylinder with respect to said support means.

3. The assembly of claim 2 wherein said wheel assemblies each comprise acaster mounted to said frame by an arm.

4. A support assembly for providing internal support for a horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to significantly deform or collapse if without supportcomprising a plurality of wheel assemblies attached to a frame member,each wheel of said wheel assemblies comprising a pneumatic wheel andbeing positioned so that it contacts the inner surface of said cylinder,and

means rotatably contacting the lower external surface of said cylinder.

5. The assembly of claim 2 wherein said frame is an axially mounted rodattached to said forming apparatus.

6. The assembly of claim 3 wherein said arm is adjustable in length.

7. A support assembly for providing internal support for preventingexcessive deformation or collapse of large diameter thin-walledcylinders formed horizontally and helically from metal strip, saidassembly comprising a frame stationarily supported with respect to saidforming apparatus to prevent rotational movement of said frame and axialmovement thereof in the direction of the axis of said cylinder,

a plurality of circumferentially and axially spaced wheel assembliesattached to said frame for allowing continuous rotation and axial motionof said cylinder with respect to said wheel assemblies, each of saidwheel assemblies having at least one wheel, each wheel beingsubstantially equidistant from the axis of said cylinder and spaced fromsaid axis for contacting a different portion of the inner surface ofsaid cylinder,

support means fixed with respect to said frame member for contacting thelower external surface of said cylinder for allowing continuous rotationand axial motion of said cylinder with respect to said support means.

8. A support assembly for providing internal support for a horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to deform or collapse if without support, said supportassembly being held in a fixed relationship with respect to a formingapparatus, said assembly comprising at least two external support wheelassemblies mounted below the horizontal mid-point of said cylinder ondifferent sides of the vertical mid-point of said cylinder,

a frame fixedly attached with respect to said forming apparatus toprevent movement of said frame in the direction of the axis of saidcylinder and to prevent rotation of the frame with respect to saidforming apparatus, and

a plurality of internal wheel assemblies attached to said frame, atleast two of said internal wheel assemblies being, located adjacent saidexternal wheel assemblies and further having at least one additionalwheel assembly mounted above the horizontal mid-point of said cylinder.

9. The assembly of claim 8 wherein said internal wheel assemblies eachcomprise a caster mounted to said frame by an arm.

10. The assembly of claim 8 wherein said internal wheel assemblies eachincludes pneumatic wheels.

1 l. The assembly of claim 8 wherein said frame is an axially mountedshaft affixed to said forming apparatus.

12. A support assembly for providing internal support for a horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to deform or collapse if without support, said supportassembly being held in a fixed relationship with respect to a formingapparatus, said assembly comprising at least one external support wheelassembly mounted below the horizontal mid-point of said cylinder atsubstantially the vertical mid-point of said cylinder,

a plurality of external rotary support means mounted to contact thelower exterior of said cylinder on different sides of the verticalmid-point of said cylinder,

a frame fixedly attached with respect to said forming apparatus toprevent movement of said frame in the direction of the axis of saidcylinder and to prevent rotation of the frame with respect to saidforming apparatus, and

a plurality of internal wheel assemblies attached to said frame, atleast one of said internal wheel assemblies being located adjacent theinner surface of said cylinder opposite said external wheel assembly,and at least two of said internal wheel assemblies extending above themid-point of said cylinder and contacting the upper interior surface ofsaid cylinder.

13. A support assembly for providing support for a length of horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to deform or collapse if in a horizontal position withoutsupport, said support assembly being positioned away from a formingapparatus to support said length of cylinder after it has been cut froma cylinder being formed by said apparatus, said assembly comprising atleast one external support wheel assembly mounted below the horizontalmid-point of said cylinder at substantially the vertical mid-point ofsaid cylinder,

a plurality of external rotary support means mounted to contact thelower exterior of said cylinder on different sides of the verticalmid-point of said cylinder, a frame, and a plurality of internal wheelassemblies attached to said frame, at least one of said internal wheelassemblies being located adjacent the inner surface of said cylinderopposite said external wheel assembly, and at least two of said internalwheel assemblies extending above the mid-point of said cylinder andcontacting the upper interior surface of said cylinder.

14. A support assembly for providing support for a length of horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to deform or collapse if in a horizontal position withoutsupport, said support assembly being positioned away from a formingapparatus to support said length of cylinder after it has been cut froma cylinder being formed by said apparatus, said assembly comprising atleast two external support wheel assemblies mounted below the horizontalmid-point of said cylinder, each of said assemblies being spaced fromthe vertical mid-point of said cylinder, and

a plurality of internal wheel assemblies attached to a frame, said framebeing affixed so as to prevent axial and rotational movement of saidframe with respect to said forming apparatus, a portion of said wheelassemblies being positioned to contact the interior of said cylindersubstantially at the area of contact of each of said external wheelassemblies, and the other of said internal wheel assemblies extending.above said horizontal axis of said cylinder and contacting the upperinterior surface of said cylinder.

15. The assembly of claim 14 wherein internal wheel assemblies within aplane normal to the axis of the cylinder are substantiallysymmetricylinder.

16. The assembly of claim 15 wherein each of the sets of wheelassemblies within said plane has two wheel assemblies below thehorizontal axis of said cylinder and three wheel assemblies above thishorizontal axis.

17. A support assembly for providing internal support for a horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to significantly deform or collapse if without supportcomprising a plurality of circumferentially and axially spaced wheelassemblies attached to a frame member for allowing continuous rotationand axial motion of said cylinder with respect to said wheel assemblies,

each wheel of said wheel assemblies being positioned for contacting adifferent portion of the inner surface of said cylinder, and

support means disposed beneath said wheel assemblies for contacting thelower external surface of cal about a vertical axis through the axis ofthedifferent portion of the inner surface of said cylinder, and

exterior support means fixed with respect to said frame member forcontacting the lower external surface of said cylinder for allowingrotation and axial motion of said cylinder with respect to said supportmeans.

1. A support assembly for providing internal support for a horizontal,large diameter cylinder having a wall thickness such that said cylinderis likely to significantly deform or collapse if without supportcomprising a plurality of circumferentially and axially spaced wheelassemblies attached to a frame member for allowing continuous rotationand axial motion of said cylinder with respect to said wheel assemblies,each wheel of said wheel assemblies being positioned for contacting adifferent portion of the inner surface of said cylinder, and supportmeans fixed with respect to said frame member for contacting the lowerexternal surface of said cylinder for allowing continuous rotation andaxial motion of said cylinder with respect to said support means.
 2. Asupport assembly for providing internal support for a horizontal, largediameter cylinder having a wall thickness such that said cylinder islikely to significantly deform or collapse if without support, saidsupport assembly being held in a fixed relationship with respect to aforming apparatus, said assembly comprising a frame stationarilysupported with respect to said forming apparatus to prevent rotationalmovement of said frame and axial movement thereof in the direction ofthe axis of said cylinder, a plurality of circumferentially and axiallyspaced wheel assemblies attached to said frame for allowing continuousrotation and axial motion of said cylinder with respect to said wheelassemblies, each of said wheel assemblies having at least one wheel,each wheel being substantially equidistant from the axis of saidcylinder and spaced from said axis for contacting a different portion ofthe inner surface of said cylinder, and support means fixed with respectto said frame member for contacting the lower external surface of saidcylinder for allowing continuous rotation and axial motion of saidcylinder with respect to said support means.
 3. The assembly of claim 2wherein said wheel assemblies each comprise a caster mounted to saidframe by an arm.
 4. A support assembly for providing internal supportfor a horizontal, large diameter cylinder having a wall thickness suchthat said cylinder is likely to significantly deform or collapse ifwithout support comprising a plurality of wheel assemblies attached to aframe member, each wheel of said wheel assemblies comprising a pneumaticwheel and being positioned so that it contacts the inner surface of saidcylinder, and means rotatably contacting the lower external surface ofsaid cylinder.
 5. The assembly of claim 2 wherein said frame is anaxially mounted rod attached to said forming apparatus.
 6. The assemblyof claim 3 wherein said arm is adjustable in length.
 7. A supportassembly for providing internal support for preventing excessivedeformation or collapse of large diameter thin-walled cylinders formedhorizontally and helically from metal strip, saiD assembly comprising aframe stationarily supported with respect to said forming apparatus toprevent rotational movement of said frame and axial movement thereof inthe direction of the axis of said cylinder, a plurality ofcircumferentially and axially spaced wheel assemblies attached to saidframe for allowing continuous rotation and axial motion of said cylinderwith respect to said wheel assemblies, each of said wheel assemblieshaving at least one wheel, each wheel being substantially equidistantfrom the axis of said cylinder and spaced from said axis for contactinga different portion of the inner surface of said cylinder, support meansfixed with respect to said frame member for contacting the lowerexternal surface of said cylinder for allowing continuous rotation andaxial motion of said cylinder with respect to said support means.
 8. Asupport assembly for providing internal support for a horizontal, largediameter cylinder having a wall thickness such that said cylinder islikely to deform or collapse if without support, said support assemblybeing held in a fixed relationship with respect to a forming apparatus,said assembly comprising at least two external support wheel assembliesmounted below the horizontal mid-point of said cylinder on differentsides of the vertical mid-point of said cylinder, a frame fixedlyattached with respect to said forming apparatus to prevent movement ofsaid frame in the direction of the axis of said cylinder and to preventrotation of the frame with respect to said forming apparatus, and aplurality of internal wheel assemblies attached to said frame, at leasttwo of said internal wheel assemblies being located adjacent saidexternal wheel assemblies and further having at least one additionalwheel assembly mounted above the horizontal mid-point of said cylinder.9. The assembly of claim 8 wherein said internal wheel assemblies eachcomprise a caster mounted to said frame by an arm.
 10. The assembly ofclaim 8 wherein said internal wheel assemblies each includes pneumaticwheels.
 11. The assembly of claim 8 wherein said frame is an axiallymounted shaft affixed to said forming apparatus.
 12. A support assemblyfor providing internal support for a horizontal, large diameter cylinderhaving a wall thickness such that said cylinder is likely to deform orcollapse if without support, said support assembly being held in a fixedrelationship with respect to a forming apparatus, said assemblycomprising at least one external support wheel assembly mounted belowthe horizontal mid-point of said cylinder at substantially the verticalmid-point of said cylinder, a plurality of external rotary support meansmounted to contact the lower exterior of said cylinder on differentsides of the vertical mid-point of said cylinder, a frame fixedlyattached with respect to said forming apparatus to prevent movement ofsaid frame in the direction of the axis of said cylinder and to preventrotation of the frame with respect to said forming apparatus, and aplurality of internal wheel assemblies attached to said frame, at leastone of said internal wheel assemblies being located adjacent the innersurface of said cylinder opposite said external wheel assembly, and atleast two of said internal wheel assemblies extending above themid-point of said cylinder and contacting the upper interior surface ofsaid cylinder.
 13. A support assembly for providing support for a lengthof horizontal, large diameter cylinder having a wall thickness such thatsaid cylinder is likely to deform or collapse if in a horizontalposition without support, said support assembly being positioned awayfrom a forming apparatus to support said length of cylinder after it hasbeen cut from a cylinder being formed by said apparatus, said assemblycomprising at least one external support wheel assembly mounted belowthe horizontal mid-point of said cylinder at substantially the verticalMid-point of said cylinder, a plurality of external rotary support meansmounted to contact the lower exterior of said cylinder on differentsides of the vertical mid-point of said cylinder, a frame, and aplurality of internal wheel assemblies attached to said frame, at leastone of said internal wheel assemblies being located adjacent the innersurface of said cylinder opposite said external wheel assembly, and atleast two of said internal wheel assemblies extending above themid-point of said cylinder and contacting the upper interior surface ofsaid cylinder.
 14. A support assembly for providing support for a lengthof horizontal, large diameter cylinder having a wall thickness such thatsaid cylinder is likely to deform or collapse if in a horizontalposition without support, said support assembly being positioned awayfrom a forming apparatus to support said length of cylinder after it hasbeen cut from a cylinder being formed by said apparatus, said assemblycomprising at least two external support wheel assemblies mounted belowthe horizontal mid-point of said cylinder, each of said assemblies beingspaced from the vertical mid-point of said cylinder, and a plurality ofinternal wheel assemblies attached to a frame, said frame being affixedso as to prevent axial and rotational movement of said frame withrespect to said forming apparatus, a portion of said wheel assembliesbeing positioned to contact the interior of said cylinder substantiallyat the area of contact of each of said external wheel assemblies, andthe other of said internal wheel assemblies extending above saidhorizontal axis of said cylinder and contacting the upper interiorsurface of said cylinder.
 15. The assembly of claim 14 wherein internalwheel assemblies within a plane normal to the axis of the cylinder aresubstantially symmetrical about a vertical axis through the axis of thecylinder.
 16. The assembly of claim 15 wherein each of the sets of wheelassemblies within said plane has two wheel assemblies below thehorizontal axis of said cylinder and three wheel assemblies above thishorizontal axis.
 17. A support assembly for providing internal supportfor a horizontal, large diameter cylinder having a wall thickness suchthat said cylinder is likely to significantly deform or collapse ifwithout support comprising a plurality of circumferentially and axiallyspaced wheel assemblies attached to a frame member for allowingcontinuous rotation and axial motion of said cylinder with respect tosaid wheel assemblies, each wheel of said wheel assemblies beingpositioned for contacting a different portion of the inner surface ofsaid cylinder, and support means disposed beneath said wheel assembliesfor contacting the lower external surface of said cylinder for allowingcontinuous rotation and axial motion of said cylinder with respect tosaid support means.
 18. A support assembly for providing internalsupport for a horizontal, large diameter cylinder having a wallthickness such that said cylinder is likely to significantly deform orcollapse if without support, comprising a plurality of wheel assemblymeans for supporting said cylinder while allowing continuous rotationand axial movement of said cylinder with respect to said wheel assemblymeans, said wheel assembly means being attached to a frame member andcomprising a plurality of circumferentially and axially spaced wheelassemblies, each wheel of said wheel assemblies being positioned forcontacting a different portion of the inner surface of said cylinder,and exterior support means fixed with respect to said frame member forcontacting the lower external surface of said cylinder for allowingrotation and axial motion of said cylinder with respect to said supportmeans.